1. Field of Invention
The present invention relates to electrostatic copiers.
More particularly, the invention relates to an arrangement for transporting toner particles from a supply to a latent-image developing station of an electrostatic copier.
Specifically, the invention relates to an arrangement of the type in question, which permits the amount of toner that is supplied to the developing station per unit time, to be selectively varied.
2. The Prior Art
An arrangement of this general type is known from German Allowed Application No. 1,954,323. There, toner particles are received in a container having a perforated bottom. A brush rotates in the container and its bristles enter the perforations and permit toner particles to fall through the same and onto a conveyor. The amount of particles supplied per unit time can be varied by varying the speed of rotation of the brush; the number of revolutions of the brush can be varied stepwise or intermittently by a certain extent per unit time.
The arrangements for effecting these stepwise or intermittent adjustments are rather complicated and therefore expensive. Moreover, they do not permit small adjustments; only rather imprecise ones which, therefore, result in similarly imprecise variations in the quantity of toner that is forwarded for unit time.